Moving stairway



Aug. 19, 1941. H, v, MCCORMICK 2,253,386

MOVING STAIRWAY Filed Dec. 7, 1940 4a 40 32 .46 4% A? "2 K a/ 4 T437; 20 222 WITNESSES: INYEN'II'OR 4%. 49. Ham/d kwwamr/r.

ATTORNEY Patented Aug. 19, 1941 2,253,386 MOVING STAIRWAY Harold V. McCormick, Westfield, N. J., assignor to Westinghouse Electric Elevator Company, Jersey City, N. J., a corporation of Illinois Application December 7, 1940, Serial No. 369,024

8 Claims. gel. 198-16) My invention relates to moving Stairways, and, more particularly, to the handrails of such stairways and the driving means for moving them in accordance with the movement of the stairway steps.

One object of my invention is to provide a stairway handrail drive which may be easily and economically manufactured, installed, and maintained in operation, and which may be used in a simple, narrow balustrade.

Another object is to provide a stairway handrail unit which shall not require additional tensioning wheels.

A further object is to provide a driving means for stairway handrails which will continue to move the handrails in accordance with the movement of the steps, even after the handrails stretch and become slack.

A further object is to provide a handrail driving means which may be mounted in a small space in the stairway.

It is also an objectof my invention to provide a. handrail driving means which will eliminate the necessity of keeping the handrails under constant tension.

Other objects of the invention will, in part, be

obvious and will, in part, appear in the following description taken in connection with the accompanying drawing, in which: Figure 1 is a skeleton-like View in side elevation of a moving stairway provided with a handrail driving mechanism constructed in accordance with my invention;

Fig. 2 is an enlarged View in side elevation of the driving wheel for moving the handrail illustrated in Fig. 1, with part of the cam wheel shown in cross section; and

Fig. 3 is an enlarged view taken along. the line III-III of Fig. 2.

Referring more particularly to the drawing, I have illustrated a moving stairway as embodying an endless series of movable steps I disposed to be moved along a plurality of tracks (not shown) by a gear chain 2 between an upper landing 3 and a lower landing 4. The gear chain may be supported at the lower landing and at the upper landing by suitable sprocket Wheels 5 and 6. The sprocket wheel and ear chain may be driven in any suitable manner as by a motor (not shown) connected to the shaft 1 upon which the sprocket Wheels 6 are mounted. Any suitable truss or frame (not shown) may be provided for supporting the moving steps between the upper landing and the lower landing. Th se cons ruc ions ar well known.

A traveling handrail 9 is provided at each side of the steps to move with the steps and at approximately the same speed as the steps.

The handrail may be constructed of a plurality of layers of strips of textile material, such as canvas, which may be held together'by impregnating them with rubber or rubber-like material and vulcanizing them to constitute an endless beltlike body of flexible resilient material of approximately C-shape in cross section.

The handrail 9 is mounted upon a newel wheel H at the lower landing and upon a driving newel wheel 12 at the upper landing. A guide rail I3 is placed underneath the upper section of the handrail between the newel wheels for supporting and guiding the upper portion of the handrail in its movement from one newel wheel to the other in a manner well known in the art. In like manner a guide rail I4 is mounted above the lower section of the handrail for guiding and supporting it on its return travel from one newel wheel to the other. A sprocket chain l5 (Fig. 1) is disposed over a sprocket wheel I6 fixed to the chain gear driving wheel and over a sprocketwheel l8 fixed by a key 2| on the hub IQ of the driving wheel 12 which is rotatably mounted on a shaft 20, (Fig. 3).

Inasmuch as considerable difliculty has heretofore been experienced in maintaining the handrails under sufficient tension to cause the drivingwheel to move them exactly in accordance with the movement of the steps, it has usually been necessary to include additional sheaves and 1 tensioning wheels to provide sufficient friction between the driving wheels and the handrails to move the handrails in accordance with the movement of the steps.

In order to increase the traction between the driving newel wheel and the handrail without requiring tensioning devices, I have mounted a plurality of movable fingers 22 and 23 on the drivin wheel for engaging the inner side walls of the handrail as it is carried around by the wheel.

The inner end of the finger 23, shown in Fig. 3, is pivotally mounted by a pin 24 in a lug 25 disposed on the side of the driving wheel. Its outer end extends toward the rim 26 of the driving wheel and is provided with an outwardly extending tip 21 having a rounded surface suitable fgrlegngaging the inner side wall 28 of the handr The finger 22 shown in Fig. 3 is pivotally mounted by a pin 30 on a lug 3| on the side of the wheel opposite to that of the lug 25 and further away from the hub 19 than the lug 25. The free end of the finger 22 extends toward the rim 26 and is provided with an outwardly extending rounded portion 21a disposed to engage the inner face of .the left-hand side of the handrail 9. A biasing spring 32 is mounted between the free ends of the fingers 22 and 23 by means of a socket 33 in the finger 22a, and a socket 34 in the finger 23. The spring 32 should be of such length and such strength as to press the free ends of the fingers outwardly into frictional engagement with the inner side walls of the handrail 9.

A link 35 is provided for connecting the fingers 22a and 23a to equalize their movements toward and away from the driving wheel. The lefthand end of the link 38 is pivotally connected by a pin 31 .to the inner end of the finger 22a, and the right-hand end of the link is pivotally connected by pin 38 to the middle section of the finger 23. It will be obvious that the link will cause the fingers to move in unison either toward or away from each other, as either one is moved transversely.

A suificient number of pairs of fingers should be mounted on the driving wheel to ensure the engagement of a plurality of fingers with the handrail at any given time.

In order to move the fingers inwardly so that they may enter the interior of the handrail at the point where it moves into engagement with the driving wheel, each of the fingers 22 on the left-hand side of the driving wheel (Fig. 3) is provided with an outwardly extending arm 40 disposed to engage a non-rotating cam 4| which is fixed to a portion of a frame 42. A roller 43 is mounted on the outer end of the arm 40 to engage the face of the cam 4| and thereby decrease the friction between the cam and the arms.

By referring to Fig. 1, it will be seen that the cam shoulder 44 extends from the point where the handrail leaves the driving wheel to the point Where it approaches the driving wheel and that it will be engaged by the rollers 43 on the fingers 22 as the driving wheel is rotated and thus force the fingers inwardly toward the wheel and into their retired position as the handrail leaves the driving wheel.

Assuming that the driving wheel is rotating in the direction of the arrow 45, as shown in the lower part of Fig. 2, it will be observed that the roller 43 engages the cam shoulder 44 as the driving wheel is rotated and thereby moves the arm 40 to move the free end of the finger 22 inwardly away from the side wall of the handrail. The inward movement of the finger 22 causes the link 36 to pull the free end of the finger 23 inwardly toward the driving wheel at the same time so that both of the finger tips 21 and 2112 are withdrawn from engagement with the inner side walls of the handrail. Thus as the driving wheel continues its rotation, the fingers 2'! and 21a are enabled to move out of the interior of the handrail without touching it.

The fingers are forced into the retired position by the cam to eliminate any possibility of sticking fingers failing to get out of the path as the handrail leaves the sheave.

It will be observed that the shoulder 44 extends to the point where the upper section of the handrail is making its tangential contact with the driving wheel, thereby maintaining the finger tips 21a and 21 in their retired position until they travel to a position within the interior of the handrail. As soon as the fingers are wlthin the interior of the handrail, the shoulder 44 falls away to the lesser surface 46 of the cam 4|. This action permits the roller 43 to move toward the hub l9 of the driving wheel under the action of the biasing spring 32, and thus permits the biasing spring to move the finger tips 21 and 21a into engagement with the inner faces of the side walls .of the handrail, in which position they increase the traction between the driving wheel and the handrail.

By this arrangement, it will be seen that the fingers are successively advanced into contact with the handrail just after it contacts the driving wheel and are successively retired just before the handrail leaves the driving wheel. Thus, the handrail is driven by a combination of friction between the outer surface of the driving wheel and the handrail and by the friction between the spring pressed fingers and the handrail.

The friction of the spring pressed fingers added to the friction of the rim of the driving wheel provides sufficient traction to move the handrail in accordance with the movement of the steps, regardless of whether it is under tension or has stretched to such an extent that it is even slack.

It will be obvious that the foregoing mechanism will eliminate the necessity for complex reeving involving a plurality of sheaves or wheels and that it will also eliminate the necessity for wide balustrades.

Although I have illustrated and described only one specific embodiment of my invention, it is to be understood that changes therein and modifications thereof may be made without departing from the spirit and scope of the invention.

I claim as my invention:

1. A moving stairway comprising an endless series of movable steps, a handrail, means for supporting the handrail adjacent to the stairway, a driving Wheel for driving the handrail in accordance with the movement of the steps, a plurality of fingers pivotally mounted on the driving wheel with their free ends extending toward the rim of the driving wheel, and means for moving the ends of the fingers into engagement with the handrail as it travels around with the driving wheel for increasing the traction between the driving wheel and the handrail.

2. A moving stairway comprising an endless series of movable steps, a handrail, means for supporting the handrail along one side of the steps, a driving wheel for moving the handrail in accordance with the steps, a plurality of fingers pivotally mounted on the driving wheel with their outer ends disposed toward rim of the driving wheel, means for moving the outer ends of the fingers into contact with the inner sides of the handrail as it engages the driving wheel, and means for withdrawing the fingers from contact with the handrail as it leaves the driving wheel.

3. A moving stairway comprising an endless series of movable steps, a handrail of approximately C-shape in cross section, means for supporting the handrail adjacent to the steps, a driving wheel for engaging the inner face of the handrail to move it in accordance with the movement of the steps, a plurality of fingers pivotally mounted on the driving wheel with their free ends extending toward the periphery of the wheel, means for moving the fingers into contact with the inner side walls of the handrail as it engages the wheel and for moving them out of contact with the handrail as it leaves the wheel.

4. A moving stairway comprising an endless series of movable steps, a handrail of substantially C-shape in cross section, means for supporting the handrail adjacent to the steps, a driving wheel for moving the handrail in accordance with the movement of the steps, a plurality of fingers pivotally mounted on each side of the driving wheel with their free ends disposed toward the periphery of the wheel, biasing devices for biasing the free ends of the fingers outwardly from the wheel into contact with the inner side walls of the handrail, and a cam for causing the free ends of the fingers to move inwardly toward the wheel as the handrail leaves it,

5. A moving stairway comprising an endless series of movable steps, a: handrail of approximately C-shape in cross section, a newel wheel at one end of the stairway for supporting the handrail, a driving newel wheel at the other end of the stairway for supporting and moving the handrail, power means for rotating the driving wheel in accordance with the movement of the steps, a plurality of fingers having their 'innor ends pivotally mounted on one side of the driving wheel and their outer ends extending toward the rim of the driving wheel, spring means for biasing the free ends of the fingers away from the wheel and into engagement with the inner sides of the handrail, an arm attached to each finger and disposed to extend outwardly from the finger, and a cam fixed at one side of the driving wheel in position to engage the outer ends of the arms as the driving wheel rotates and thereby force the fingers inwardly out of the way of the side walls of the handrail as it leaves the driving wheel.

6. A moving stairway comprising an endless series of movable steps, a handrail for the steps having an endless body of flexible material, said handrail being of approximately C-shape in cross section, a newel wheel for supporting the handrail at one end of the stairway, a driving wheel for supporting and driving the handrail at the other end of the stairway, power means for rotating the wheel in accordance with the movement of the steps, a plurality of fingers disposed on each side of the wheel, each finger having its inner end pivotally mounted on the driving wheel, spring means for biasing the free ends of the fingers outwardly to engage the inner faces of the side walls of that portion of the handrail engaging the driving wheel, a plurality of links connecting the fingers on one side of the driving wheel with the fingers on the other side of the driving wheel to equalize their movements in opposite directions, an outwardly extending arm disposed on each of the fingers on one side of the wheel, a roller rotatably disposed on the outer end of each arm, and a cam fixedly mounted beside the wheel for engaging the rollers as the wheel is rotated to force the free ends of the fingers inwardly out of engagement with the handrail as it leaves the driving wheel.

7. A driver for the handrails of moving stairways comprising a wheel, a plurality of fingers pivotally mounted on the body of the wheel with their free ends disposed toward the periphery of the wheel, and a cam for controlling the movement of the free ends of the fingers relative to the wheel.

8. A driver for the handrails of moving stairways comprising a wheel, a plurality of fingers pivotally mounted on each side of the Wheel with their free ends extending toward the periphery of the wheel, a plurality of links connecting the fingers on one side of the wheel and the fingers on the other side of the wheel to equalize their movements, a plurality of springs for biasing the free ends of the fingers away from the wheel, and a cam for controlling the movement of the free ends of the fingers away from the wheel.

HAROLD V. MCCORMICK. 

